Watch lubrication system



March l2, 1963 A. J. BODY 3,080,703

WATCH LUBRICATION SYSTEM Filed Jan. 12, 1961 Jb "B e w F 5 u N i u E aE- l v LQ a VN s; Q il, w Q

INVEN TOR. ALBERT J BODY United States Patent 3,080,703 WATCHLUBRICATION SYSTEM Albert `osepll Body, Waterbury, Conn., assigner toThe United States Time Corporation, Waterbury, Conn., a corporation ofConnecticut Filed Jan. 12, 1961, Ser. No. 82,201 Claims. (Cl. 58-140)This invention is in the field of lubrication systems for watches andclocks and in particular relates to apparatus and meth-ods forpreserving lubricant in the balance pivot stud recesses.

It is known that watches and clocks of the oscillating balancewheel-hairspring variety occasionally fail to function properly after ashort period of use because of the occurrence of a condition ofinsufficient lubricant in the balance wheel stud recesses. I have foundthat one reason for this condition is that there is creepage oflubricant out of the pivot stud recesses on to both the watch frame andthe balance wheel assembly until the initial quantity of lubricantstored in the recesses has been dispersed in large part to other areas.

The present invention consists of a barrier of material especiallyselected to have a high contact angle factor with respect to thelubricant. The contact angle of a given material is a physicalcharacteristic indicating whether a small droplet of liquid deposited onthe surface will flatten out and spread over a wide area or whether itwill tend to remain in spherical form. High contact angle material is ofthe form in which the uid remains as a droplet rather than as a lmspread widely over the surface of the material. I have found that when abarrier of such material is compressively attached to the end of thebalance staff it will prevent oil creepage not only across the surfaceof the barrier and around the barrier i but also between the staff andthe barrier. I have also found that annular barriers compressivelydisposed on the outer surface of the balance studs will prevent oilcreepage either across the surface of the barrier or between the barrierand the stud on to the frame members supporting the studs. Moreover,when oil barriers of this type are compressively attached to the workingmembers there is little danger of their being loosened during cleaningoperations. A further feature of importance in watches and clocks of themass produced variety is that the barriers prevent particles of brass orcopper plating from dropping into and contaminating the balancelubricating oil.

The invention may more readily be understood by reference to the singledrawing which is a partial crosssectional view of a watch or clockbalance wheel and pillar plate or frame assembly embodying the preferredform of the invention.

In the drawing the balance wheel 1 aixed to the balance staff 2 issupported for rotation by the pivots 2a in the balance studs 3 and 4which in turn are supported by the pillar plates or frames 5 and 6,respectively. The balance stud 4 is set in the balance screw 7 which isscrewed into the hairspring regulator bushing 8 staked into the pillarplate or frame 6. The balance screw 7 is provided with a slot 9 in orderthat the balance `stud 4 may be adjusted either inwardly or outwardly toprovide the proper longitudinal spacing for the balance staff. Thebalance wheel 1 is provided with the roller pin 10 which ICCintermittently receives energy from the main spring and train in theusual manner.

It is to be noted that the staff 2 is provided at its upper end with anenlarged flange portion 11 having an annular recess 12. An oversizedwasher 13 of high contact angle deformable material, preferably Teon, iscompressed on to the neck 14 of the staff and into the recess 12. I havefound than an annular Teon washer 13 having a central hole of a sizeapproximately two thousandths of an inch less than the diameter of theneck 14 and having an outside diameter approximately two thousandths ofan inch larger than the inside diameter of the recess 12, whencompressed into the recess, effectively eliminates oil creepage from thepivot seats 15 on to the staff 2 at points beyond the exposed surface ofthe barrier 13. Teon bodies also have the known property of highresistance to deterioration by lubricating oils and cleaning slolutionsof the types commonly used with watches. These properties are set forthin U.S. Patents 2,392,388, 2,392,- 389 and 2,559,750.

At the opposite end of the staff 2 is seen the hairspring hub or collet16 which carries the inner end of the hairspring 16a. The outer end ofthe collet 16 is similarly provided with a recess 17 into which iscompressed another oversized Teon washer 18 as above described.

Both washers are preferably of greater thickness than the depth of therecesses to provide a longer oil creepage path than would be obtained ifthey were flush with the surface of the recesses.

To further prevent oil creepage from the pivot cavities 15 of thebalance studs, the inner ends of the studs 3 and 4 projecting beyond thepillar plates are also provided with undersized Teflon washers 20 and 21stretched over the studs. The oil 19 is thus confined to the pivots andthe balance stud cavities 15 as desired.

What is claimed is:

l. ln a timekeeping device lubricated by a liquid lubricant, thecombination of a rotating shaft having a bearing surface disposedthereon, and an annular washer of deformable material having an internaldiameter less than the outer diameter of said shaft disposed on theshaft adjacent to the bearing surface, said washer being of materialhaving a high contact angle relative to the lubricant.

2. ln a timekeeping device lubricated by a liquid lubricant, thecombination of a rotating shaft, said shaft having a bearing surfacethereon, and an annular washer of deformable material having an internaldiameter less than the outer diameter of said shaft disposed on theshaft adjacent to the bearing surface and a rigid retaining membersurrounding the outer` surface of said washer compressively engaging thewasher to bias said washer against the shaft, said washer being ofmaterial having a high contact angle relative to the lubricant.

3. In a timekeeping device lubricated by a liquid lubricant, thecombination of a rotating shaft having a bearing surface thereon, alubricant retaining bearing member within which said shaft is disposedfor rotation, a frame member adapted to support said bearing member, afirst annular washer of deformable material having an internal diameterless than the outer diameter of said shaft disposed on the shaftadjacent to the bearing surface and a second annular washer ofdeformable material having an internal diameter less than the outerdiameter of said bearing member disposed on the outer surface of theYbearing member between the frame and the end of the bearing member,said annular washers being of material having a high contact anglerelative to the lubricant.

4. In a timekeeping device lubricated by a liquid lubricant, thecombination of a liquid retaining cavity, a rotating shaft having abearing surface at its end, and a material having a high contact anglerelative to the lubricant compared to the shaft, wherein the highcontact angle ma@ terial is secured onto the shaft adjacent to thebearing sur-y face, whereby the lubricant in the cavity is preventedfrom 10 migrationl up the shaft by the high contact angle material.

5. The combination as in claim 4 in which said material 5 cleaningsolvents.

References Cited in the lile of this patent FOREIGN PATENTS 302,967Switzerland Jan. 17, 1955

1. IN A TIMEKEEPING DEVICE LUBRICATED BY A LIQUID LUBRICANT, THECOMBINATION OF A ROTATING SHAFT HAVING A BEARING SURFACE DISPOSEDTHEREON, AND AN ANNULAR WASHER OF DEFORMABLE MATERIAL HAVING AN INTERNALDIAMETER LESS THAN THE OUTER DIAMETER OF SAID SHAFT DISPOSED ON THESHAFT ADJACENT TO THE BEARING SURFACE, SAID WASHER BEING OF MATERIALHAVING A HIGH CONTACT ANGLE RELATIVE TO THE LUBRICANT.